Vitamin B9, folic acid or folate... We take stock!

If you are pregnant or planning to become pregnant, your doctor has probably recommended that you supplement with folic acid or vitamin B9. But is there a difference? Why is it so important? And how do you choose the right one? Let's take a look.

Why is vitamin B9 so important before and during pregnancy?

Vitamin B9 plays multiple roles in the body, particularly during the perinatal period. It is involved in all processes of cell growth and division, and is essential for embryo formation and fetal development.

Nutritional data available in France show that vitamin B9 intake is often insufficient in women of childbearing age. This is why the Haute Autorité de Santé (HAS) recommends that pregnant women or women wishing to become pregnant supplement with 400 µg per day, at least one month before conception.

1. It contributes to the growth of maternal tissues

This is the officially recognized claim by the EFSA: "Folates contribute to maternal tissue growth during pregnancy." This function notably covers the formation of the placenta and the development of the uterus.

2. It contributes to normal blood formation and immune system function

Vitamin B9 contributes to the formation of red blood cells and the normal functioning of the immune system, two officially recognized claims by the EFSA. It also contributes to the normal synthesis of amino acids, essential for cell growth.

3. Its role in reducing the risk of neural tube defects

The neural tube is the origin of the fetus's central nervous system, and its closure occurs a few weeks after fertilization, often even before pregnancy is confirmed. This is why the HAS recommends supplementation as soon as pregnancy is desired, without waiting.

This recommendation is based on a claim officially authorized by the European Commission (EU Regulation n°1135/2014): folate supplementation contributes to increasing maternal folate status, an insufficient folate status being a recognized risk factor in the development of neural tube defects in the fetus. This claim applies to supplements providing at least 400 µg of folates per day, for women of childbearing age, with a daily intake maintained for at least one month before conception and up to three months after.

The human body cannot synthesize vitamin B9. The body's reserves are therefore naturally limited, which makes a regular daily intake, through food and, if necessary, supplementation, particularly important during the perinatal period.

 

Vitamin B9, folic acid or folates: what are the differences?

Folic acid, folates, vitamin B9… These are all terms that refer to the same B vitamin. But there are two distinct forms, with very different assimilation profiles.

Folic acid: the synthetic version

Folic acid is the synthetic form of vitamin B9, manufactured in the laboratory. Easy to produce and stable, it is commonly used in food supplements and fortified foods.

However, its metabolism is complex: once absorbed, folic acid goes through several enzymatic transformation steps in the liver before it can be used by the body. The liver's capacity to manage this transformation is limited. Moreover, in some people, particularly those carrying a MTHFR gene mutation, this activation does not occur correctly, which can make folic acid supplementation less effective.

Folates: the natural and directly assimilable form

Folates are the natural form of vitamin B9, present directly in foods. Unlike folic acid, they do not require enzymatic transformation before being used by the body: a large part is directly bioavailable.

The most advanced form of folates in supplementation is 5-MTHF (methylfolate), notably in the patented form Quatrefolic®. This is the active form of vitamin B9, directly usable by the body without a conversion step, including in people carrying the MTHFR mutation.

Why choose folates rather than folic acid?

For most women, and especially for those carrying the MTHFR gene mutation, supplementation in the form of folates or 5-MTHF is generally better assimilated than conventional folic acid supplementation. This is a point to discuss with your doctor based on your personal profile.

 

Where can you find vitamin B9 in food?

Food remains an important source of natural folates. However, folates are fragile: they are sensitive to light and heat. Depending on cooking methods, the naturally present folate content in foods can decrease significantly. This is why appropriate supplementation often complements dietary intake, particularly before and during pregnancy.

Foods very rich in folates

• Liver (not recommended during pregnancy due to its vitamin A content)
• Baker's yeast
• Spinach, watercress, lamb's lettuce, chicory, dandelion
• Melon
• Seeds: walnuts, chestnuts, chickpeas
• Aged cheeses: brie, blue, goat

Foods moderately rich in folates

• Leafy vegetables: lettuce, endives, cabbage, leeks
• Green and white beans, lentils, peas
• Asparagus, beetroot, zucchini, avocados

For a complete list of vitamin B9 content per food, consult the Ciqual nutritional composition table from ANSES.

 

Vitamin B9 supplementation: when and at what dose?

In addition to dietary folates, the HAS recommends that women wishing to conceive supplement with 400 µg per day, starting at least one month before conception and continuing until the end of the first trimester of pregnancy.

If you have any doubts about possible vitamin B9 deficiencies, do not hesitate to ask your doctor for a blood test to check your blood level. Indeed, you can feel healthy and yet not have sufficient vitamin B9 intake. A severe deficiency can manifest as "megaloblastic" anemia (fatigue, headaches, dizziness, shortness of breath, pallor); if you experience these symptoms, consult your doctor.

For more information on vitamin B9 and food supplements during pregnancy, consult our guide: Pregnancy and Food Supplements.

 

Frequently asked questions about vitamin B9

What is the difference between folic acid, folates, and vitamin B9?

These three terms refer to the same B vitamin. "Vitamin B9" is the generic name. "Folic acid" refers to the synthetic form, manufactured in the laboratory. "Folates" refers to the natural form, present in foods and in some food supplements (such as 5-MTHF). Folates and 5-MTHF are generally better assimilated than conventional folic acid.

What is the MTHFR gene mutation?

The MTHFR gene mutation affects the body's ability to convert folic acid into its active form (5-MTHF). People carrying this mutation benefit from supplementing directly with 5-MTHF (methylfolate) rather than conventional folic acid, for better assimilation. A genetic test or a blood test performed with your doctor can determine this.

When should you start taking vitamin B9 before pregnancy?

The HAS recommends starting supplementation at least one month before conception. The neural tube of the fetus forms very early in pregnancy, often even before pregnancy is confirmed. Do not wait until you are pregnant to start.

Can your vitamin B9 needs be met solely through diet?

Dietary folates are important, but they are fragile (sensitive to heat and light) and their content varies depending on cooking methods. In practice, it is difficult to regularly meet vitamin B9 needs solely through diet during pregnancy, hence the importance of appropriate supplementation. Consult your doctor or midwife for personalized advice.

Is Quatrefolic® a natural or synthetic form?

Quatrefolic® (5-MTHF-glucosamine) is the active form of methylfolate, obtained through a chemical synthesis process. Although it is directly usable by the body like natural folates, it is of synthetic origin.

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This article is for informational purposes only and does not constitute medical advice. Consult your doctor or midwife for personalized health advice, particularly for the choice and dosage of your vitamin B9 supplementation.